The present invention relates generally to the field of arc welding, and more particularly to the field of air-cooled arc welding torches.
Arc welding is a welding process in which an electric current is used to produce localized melting in a work piece. There are many different types of arc welding processes. One example of an arc welding process is TIG (Tungsten Inert Gas) welding (also known as gas tungsten arc welding, GTAW, or HELIARC). TIG welding is a type of arc welding process in which an electric arc is maintained between a welding implement, such as a hand-held welding torch, and a metal work piece. Typically, the welding implement includes a cylindrical electrode coupled to a torch head. The arc is produced by electricity that flows between the electrode and the work piece. Typically, the electrode is comprised of tungsten. The electricity for the arc welding process is provided by a power source coupled to the torch head of the welding implement by a power cable.
The electricity flowing through the torch head may produce a substantial amount of heat. In addition, the electricity flowing through the electrode and the work piece may produce heat that is transferred to the torch head. The heat introduced into the torch head may damage the components of the torch. In addition, the heat may make the torch difficult to hold. The amount of heat produced is a function of the current flowing through the torch. The torches may be air-cooled at low current levels. However, the ability of air-cooling to sufficiently cool the torch decreases as the amount of current flowing through the torch increases. Consequently, the amount of current at which the torch is operated may be limited by the temperature increase in the torch caused by the current flowing through the torch. Therefore, liquid-cooled welding torches have been developed to remove a greater amount of the heat from within the torch head, thereby enabling the torch to be operated at higher current levels. However, liquid cooling the torch increases the cost and complexity of the torch and the welding system used to operate the torch. For example, a liquid-cooled torch requires a liquid-cooling unit to produce a flow of cooling liquid and to remove the heat from the liquid.
Therefore, a need exists for a technique to increase the ability of an air-cooled TIG welding torch to remove heat. More specifically, a need exists for a technique to enable an air-cooled welding torch to remove a greater amount of heat so that the torch may be operated at greater current levels.